Damage to dock pilings is an annual problem in climates where bodies of water are subject to seasonal freezing. Since it is often cost prohibitive or impractical to remove the piling from the ground during these seasons, the pilings are left in place in the water. As a layer of ice covers the body of water the ice freezes to the pilings. The level of underlying water in such bodies usually does not remain constant, and the layer of ice necessarily rises or falls with the change in the water level. Since the pilings are firmly frozen to the ice, the force of the shifting ice causes the pilings to be loosened or pulled from the ground.
Prior attempts to solve this problem have been made. For example, Butler U.S. Pat. No. 3,370,432 shows a tubular collar which requires a layer of an anti-freeze solution surrounding the piling. Mikolajczyk U.S. Pat. No. 3,180,099 shows a sheath containing a brass spring and a lining which is positioned around a piling and attached to the bottom of the crossboards of a dock. However, when crossboards are removed for the winter season, this device cannot be used. In another example, Straub U.S. Pat. No. 4,252,471 shows a tapered cylinder which is permanently attached to a piling and does not float at the surface of the water.